This proposal is for funds to plan and produce an application for a Center of Excellence in Molecular Hematology. The Center envisioned would be comprised of five research groups: Metal Metabolism, Cell Adhesion, Complement Regulation-Paroxysmal Nocturnal Hemoglobinuria, Cell Differentiation and Cytokines-Hematopoiesis. Thirty-two faculty members have been identified as potential participants. Two core laboratories are proposed: a stem cell-homologous recombination core and a transgenic animal core. An administrative core is also described. Facilities in place which will support the Center of Excellence in Molecular Hematology include an NIH-funded General Clinical Research Center and a Bone Marrow Transplantation Program.